Do you typically use it on a flat surface? Laptops depend on ventilation from the bottom so it's important that the vents on the bottom are completely unrestricted.

If you have used the laptop for any period of time placed on a surface such as a blanket or carpet it's possible that the fan and shroud have bee clogged up with lint and the laptop may need to be disassembled to completely clean the lint out.

It's possible that the thermal grease between the heatsink and cpu has dried out due to running hot so that may need to be cleaned out and new thermal grease applied.

As a temporary measure, you could try using one of those laptop coolers that fit under the laptop and provide extra cooling.

If the laptop is still under warranty, I would contact ASUS tech support about it and make sure it is not a known issue.

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If the thermal grease has dried out due to it being hot wouldn't that only delay the problem if I get that re-applied? ...

I didn't mean to imply that the thermal grease was the reason why the laptop is overheating but that, as a result of the laptop overheating, the thermal grease may have dried out and need to be re-done.

If the thermal grease is properly applied and system temps are maintained in the "normal" range, then the thermal grease should not typically need to be re-applied.